One vertex per element, one color per generator, with an edge from x to x·s.
(2,5)(3,7)(9,10)(11,15)(12,13)(14,16)(18,20)(21,23)(25,26,29,32)(27,30,33,37)(28,35,36,31)(34,40,39,38)(1,2,4,5)(3,6,7,8)(9,11,14,12)(10,13,16,15)(17,18,22,20)(19,21,24,23)(27,33)(30,37)(34,39)(38,40)(9,11,14,12)(10,15,16,13)(17,19,22,24)(18,23,20,21)(25,26)(27,30)(28,31)(29,32)(33,37)(34,38)(35,36)(39,40)(1,3)(2,6)(4,7)(5,8)(9,12,14,11)(10,13,16,15)(17,20,22,18)(19,21,24,23)(25,27,29,33)(26,30,32,37)(28,34,36,39)(31,38,35,40)(1,2)(3,6)(4,5)(7,8)(9,13)(10,11)(12,16)(14,15)(17,21)(18,19)(20,24)(22,23)(25,28,29,36)(26,31,32,35)(27,34,33,39)(30,38,37,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.